The invention relates to a joint comprising an inner hub, which has a longitudinal axis and inner ball tracks, and comprising an outer hub, which has a longitudinal axis and outer ball tracks, wherein the inner ball tracks and the outer ball tracks are associated with each other in pairs, and comprising a cage, which has apertures, distributed around the periphery, and which is disposed between the inner hub and the outer hub, and comprising balls, which are disposed in the apertures of the cage and in the pairs of inner ball tracks and outer ball tracks and which are held in a plane by the cage, wherein the tangential planes form an angle of inclination at the contact points of the balls with the inner ball tracks and the outer ball tracks, in which each of the inner ball tracks has an active section, in which the balls move, and in which each of the outer ball tracks has an active section, in which the balls move. The joint concerns, for example, a fixed-type universal joint or more specifically a counter track joint with alternating tracks. However, the invention is also applicable to other constant velocity ball joints.
In the prior art the ball tracks in the inner and outer hubs are generally constructed from sectors. A wide range of joints and configurations of ball tracks may be found, for example, in U.S. Pat. No. 7,591,730 (=DE 10 2004 018 721); U.S. Pat. No. 5,531,643 (=DE 42 22 205); U.S. Pat. No. 5,122,096 (=DE 39 39 531) or U.S. Pat. No. 6,872,143 (=DE 202 21 755 U1), the entire disclosures of which are incorporated herein by reference. The configuration of the joint with respect to the angle of inclination depends on a number of criteria. In order to control the balls, there should always be an angle of inclination that is greater than the self-locking angle. Furthermore, the angle of inclination should be as small as possible in order to avoid a degradation of the efficiency, a decline that is typically associated with higher pressure at the contact points. Therefore, on the one hand, the angle of inclination should be as large as possible, but, on the other hand, as small as possible. However, the increase in efficiency is especially relevant for the current efforts to reduce the emission of CO2 and to reduce the fuel requirement.